Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual o oponente em 29 de setembro de 1997?
 ###Tabelas: CREATE TABLE singles:_13_6–7 (singles:_13_6–7_id AUTO_INCREMENT PRIMARY KEY, Date VARCHAR, Tournament VARCHAR, Surface VARCHAR, Opponent VARCHAR, Score VARCHAR) CREATE TABLE casts (casts_id AUTO_INCREMENT PRIMARY KEY, Role VARCHAR, Original Broadway cast VARCHAR, Closing Broadway cast VARCHAR, Original US Tour cast VARCHAR, Original NonEquity Tour cast VARCHAR, Original São Paulo cast VARCHAR, Original Lima cast VARCHAR) CREATE TABLE winners_by_country (winners_by_country_id AUTO_INCREMENT PRIMARY KEY, Country VARCHAR, Total INT, Marathon (mens) INT, Marathon (womens) INT, Half Marathon (mens) INT, Half Marathon (womens) INT) CREATE TABLE stations_under_construction (stations_under_construction_id AUTO_INCREMENT PRIMARY KEY, Station VARCHAR, Extension VARCHAR, City/Neighborhood VARCHAR, Projected opening INT, Transit Connections VARCHAR, Park and ride? VARCHAR) CREATE TABLE architecture_support (architecture_support_id AUTO_INCREMENT PRIMARY KEY, Distribution VARCHAR, x86-64 VARCHAR, ia64 VARCHAR, ppc64 VARCHAR, sparc32 VARCHAR, hppa VARCHAR, mips VARCHAR, s390 VARCHAR, s390x VARCHAR, alpha VARCHAR, m68k VARCHAR)  
SELECT Opponent FROM singles:_13_6–7 WHERE Date = 29 september 1997